A new Harvard study on e-cigarettes has found that brand-name liquid refills for the device contain three harmful chemical flavorings, some of which is known to cause severe respiratory disease.
The study, which was published online in Environmental Health Perspectives, was conducted by researchers from the Harvard T.H. Chan School of Public Health.
Researchers found that over 75% of e-cigarette refill liquid in the market contains diacetyl, a chemical flavoring that causes bronchiolitis obliterans, a disease known as “popcorn lung” because it appeared in workers who breathed the chemical in microwave popcorn producing facilities where it was used as an artificial butter flavor.
Researchers also tested for two more harmful chemicals, acetoin and 2,3-pentanedione, which are flavoring compounds marked as “high priority” on an index of respiratory hazards in the workplace by the Flavor and Extract Manufacturers Association.
Joseph Allen, the lead study author and assistant professor of exposure assessment science, explained:
“Recognition of the hazards associated with inhaling flavoring chemicals started with ‘popcorn lung’ over a decade ago. However, diacetyl and other related flavoring chemicals are used in many other flavors beyond butter-flavored popcorn, including fruit flavors, alcohol flavors, and, we learned in our study, candy-flavored e-cigarettes.”
Allen and the Research group tested 51 types of flavored e-cigarettes and leading brand refill liquids for the presence of the three harmful chemicals. In closed chamber, a lab-built device drew air through the e-cigarette and the air was analyzed for chemicals.
The results revealed that at least one of the three harmful chemicals was found in 47 of the 51 flavors tested. Diacetyl was present in 39 of the tested flavors, Acetoin was detected in 46 flavors and 2,3-pentanedione was detected in 23 flavors.